Importance of Transient Study in Transmission Lines
A coal-fired thermal power plant experienced repeated insulation flashovers due to lightning strikes in a high-risk geographic zone. These events affected the plant’s transmission lines to a national ring network. A transient study was conducted to assess grounding system performance and lightning arrester coordination.
Problem Statement
1. Lightning-induced flashovers caused earth faults and shutdowns of a 300 MVA line.
2. Each outage resulted in a potential revenue loss of around ₹1 crore (USD 134,000) per day.
3. Lack of insulation coordination and weak grounding responses increased failure risk.
4. A transient study was needed to evaluate and strengthen surge protection and grounding.